The present invention relates to sprayers, and more particularly to an ultra-low volume (ULV) atomizing sprayer and control system.
Known in the art of spray equipment are ultra-low volume (ULV) sprayers which convert a liquid into small droplets, typically less than 50 microns in diameter, and rapidly eject the droplets in the form of a fog or cloud. This type of sprayer is frequently used in the application of liquid chemicals, such as insecticides, where the capability of large area coverage provided by the ULV sprayer is highly desirable. In these applications, the ULV sprayers are typically configured for mounting to a spray vehicle, such as a pick-up truck or all terrain vehicle, for operation of the sprayer while the spray vehicle is in motion. To facilitate the distribution of the chemical cloud or fog from the vehicle-mounted sprayer, the discharging portion of the ULV sprayer is typically inclined with respect to a supporting frame or base of the sprayer.
ULV sprayers include sprayers having gas powered engines to power a pump and a blower. The blower delivers pressurized air to a nozzle where the liquid is injected to create an aerosol fog. These sprayers tend to be bulky and heavy, frequently exceeding 40 inches in length and weighing more than 300 pounds with some exceeding 500 pounds. Furthermore, the gas powered engines and blowers of these sprayers are noisy and require substantial maintenance.
Another type of ULV sprayer uses an electric battery to power a rotating atomizing member such as a porous disk, a grooved disk or a mesh screen. In this type of sprayer, a liquid is delivered into the center of the rotating atomizing member and is forced outwardly through the member to be atomized into droplets. The atomized liquid is then expelled from the sprayer by a rapidly moving airstream generated by a fan or blower. The use of an electric power source results in a much quieter machine in contrast to a gas powered machine, particularly where a fan is used instead of a blower as the airstream generator.
The requirement of high rotational speed for the rotating atomizing member has been the source of problems for electric sprayers of the prior art. For example, porous ceramic disks have not proven to be durable and have resulted in dangerously explosive failures. Such deficiencies resulted in the need for protective barriers around the disk to contain fragments from an exploding disk which conflicts with the need for accessibility to the disk for maintenance or replacement. Furthermore, the rotating atomizing members of the prior art have also experienced sealing problems. This results in unatomized fluid leaking from the atomizing member rather than being centrifuged through the atomizing member as intended. What is needed is a quiet and compact electric powered sprayer having a durable atomizing member providing sealed operation at high rotational speeds.
ULV sprayers having a remote control are known in the art. Such devices allow for operation of a vehicle-mounted sprayer, for example, from the cab of the vehicle. Remote control devices of the prior art have provided: gas engine ignition on/off and engine start; pump on/off and spray/flush selection. Prior art remote control devices have also provided for adjustment of the pump flow rate. However, the control provided over the sprayer has been limited to manual adjustment of the sprayer. What is needed is a control system for a ULV sprayer capable of automatically controlling the sprayer for optimal operation of the sprayer. What is further needed is a control system for a ULV sprayer capable of monitoring operating parameters of various system components for diagnosis and reporting of anomalous operating parameters for enhanced operation and maintenance of the sprayer. The monitoring capabilities of the present invention provide for collection of the monitored information by a data collector for storage in a database of sprayer operating information.
According to the present invention, there is provided a sprayer having an atomizer assembly for converting a liquid into atomized droplets. The atomizer assembly includes an atomizer member, most preferably a porous disk, which is rotated by an atomizer motor to centrifugally atomize liquid delivered internally of the atomizer member. The atomizer assembly further includes an airstream generator, most preferably a motor driven fan, directing an airstream toward the atomizer member. The sprayer further includes a pump for delivering the liquid to the atomizer member from a source of the liquid. A power source is included to supply the power requirements of the atomizer assembly and pump. The sprayer includes a control and monitoring system having component control microprocessors for controlling the operation of various system components, most preferably the pump and the atomizer member. The control over the operation of system components by the control and monitoring system provides for increased efficiencies in sprayer operation.
According to an embodiment of the invention, the sprayer includes a remote controller providing for manual control of the sprayer in which a rate of flow of liquid from the pump may be selected from preset rates or variably adjusted in a range of flow rates by operation of a flow dial. The remote controller also allows for selection of automatic sprayer control in which the master control microprocessor directs the pump control microprocessor to modify the rate of flow from the pump in response to changes in sprayer velocity reported to the master control microprocessor by a velocity monitoring device.
According to one embodiment of the present invention, the control and monitoring system compares monitored information regarding operating parameters of system components against acceptable values stored in memory for diagnosis of anomalous parameters and reporting to the remote controller for display of an error code on a display of the remote controller. The sprayer may further include a data port providing access to the information processed by the control and monitoring system for storage by a data collector.